The epidemic of childhood obesity that has affected children and adolescents in this country has led to an increased prevalence of hypertension in these age groups. Analyses of the Fels Longitudinal Study (FLS) data set have shown that elevated blood pressure in childhood tracks into adulthood with fidelity and that elevated blood pressure in childhood, even within the range considered to be normal---from the 70th to the 95thpercentiles of the National CDC growth charts (2000)---accurately predict hypertension and the metabolic syndrome in adulthood. In view of the close association of obesity and hypertension and of the association of hypertension with abnormalities of cardiac structure and function, it would be of public health importance to ascertain if childhood obesity predicts abnormalities of cardiac structure and/or function later in life. We are poised to interrogate a portion of the FLS data set to address this question. The pertinent portion of the FLS data set includes serial anthropometric and blood pressure measurements from birth---and body composition measurements from age eight years---through adulthood in 750 participants who consented to undergo echocardiographic studies as adults. Hierarchical and cluster longitudinal modeling procedures will be applied to this unique set of serial measurements to elucidate the relationships between childhood obesity, blood pressure, tempo of maturation, and abnormal cardiac structure and function. The specific aims that we plan to investigate include ascertaining the effects of children's blood pressure, body size, and body composition on (1) blood pressure, (2) cardiac structure, and (3) cardiac function in the same subjects decades later as adults. We have available for analysis more than 750 echocardiographic studies from which to derive the structural measurements of left ventricular mass index (LVMI), interventricular septal thickness (IVST), and relative wall thickness (RWT) and the functional measurements of ejection fraction (EF) and left ventricular shortening fraction (LVSF). These proposed analyses have the potential to quantify risk for hypertension and abnormalities of cardiac structure and function in adulthood given certain values for body size, body composition, and blood pressure in childhood and adolescence, even if these values fall within currently accepted normal values. If we identify biomarkers in children that predict hypertension, and/or abnormal cardiac structure and function in adults, then children with these biomarkers can be evaluated more thoroughly and offered lifestyle and/or pharmacologic interventions before irreversible pathologic changes have occurred. Conversely, our proposed analyses also have the potential to identify a set of ranges of body size, body composition, and blood pressure in childhood and adolescence which are not associated with hypertension or abnormal cardiac structure and function later in life and which can be used to predict a normotensive adulthood, free of cardiac structural or functional abnormalities.